text: The radial distribution function is an important measure because several key thermodynamic properties, such as potential energy and pressure can be calculated from it.
  For a 3-D system where particles interact via pairwise potentials, the potential energy of the system can be calculated as follows:
  Where N is the number of particles in the system,  is the number density,   is the pair potential.
  The pressure of the system can also be calculated by relating the 2nd virial coefficient to  .  The pressure can be calculated as follows:
  Note that the results of potential energy and pressure will not be as accurate as directly calculating these properties because of the averaging involved with the calculation of .